Knowledge
Metrology Dictionary
The complete VIM vocabulary — all numbered concepts of JCGM 200:2012 as faithful paraphrases with clause citations — plus clearly labeled practice terms from the GUM, ILAC, ISO and NIST guidance.
Gauge R&R
A measurement systems analysis estimating the variation due to the gauge (repeatability) and the operators (reproducibility), commonly expressed as a percentage of total variation or tolerance.
AIAG MSA manual · Statistics
Normalized error (En)
The interlaboratory comparison statistic En = (x − X) / √(U²(x) + U²(X)). |En| ≤ 1 indicates agreement within expanded uncertainties; it is the standard scoring for calibration proficiency tests.
ISO 13528:2022 · Statistics
Z-score
A proficiency-testing statistic z = (x − X)/σ_pt comparing a participant result with the assigned value in units of the standard deviation for proficiency assessment; |z| ≤ 2 is conventionally satisfactory.
ISO 13528:2022 · Statistics